The 709-carat stone was extracted this week by Emmanuel Momoh, a pastor in one of the myriad churches that ministers to the mining communities of Kono district, the diamond centre that became the crucible of Sierra Leone’s blood-soaked civil war.

It is believed to be the 13th largest uncut diamond ever to be pulled from the ground, industry analysts said.

The stone is to be auctioned, the Sierra Leonean government announced yesterday, although its value cannot be determined until its quality is assessed. An 813-carat diamond was sold at closed auction in London last month for £51m.

Divine discovery: the massive diamond, on show in FreetownCredit:
AFP/GETTY IMAGES

By rights, the stone should have been found by one of the internationally-financed companies operating in the Kono diamond fields. With their huge Caterpillar bulldozers, dredges and industrial water pumps, the big firms certainly had the technological advantage.

That the discovery was instead made by one of the thousands of ordinary men and boys who toil bare-chested under the relentless equatorial sun — a man of the cloth, no less — will be taken by many as an answer to the fervent prayers whispered daily in Kono’s churches.

White Cullinan Stone found at the Cullinan diamond mine east of Pretoria. The 232-carat white diamond worth as much as $20 million was discovered at a South African mine Credit:
Getty Images

With the virtuous vicar then handing the stone to the authorities, it may also strike many as an act of propitiation, a moment when Sierra Leone symbolically distanced itself from the diamond-driven bloodlust of its 11-year civil war, which ended in 2002.

Tens of thousands of enslaved Sierra Leoneans spent much of that brutal decade hunched over hand shovels in the mud, forced to dig for diamonds to fund a rebellion mounted by a Liberian-backed warlord, Foday Sankoh.

Two children enrolled with Sierra Leonean troops fighting rebels of the Revolutionary United Front getting ready to fight on the frontline in March 2000Credit:
AFP/Getty Images

Sankoh’s Revolutionary United Front punished those who resisted it by cutting off limbs, ears and genitals or gouging out eyeballs. More than 100,000 people were killed and tens of thousands more were maimed before military intervention by Britain in 2000 turned the tide of the war in the government's favour.

The exploitation in Kono during the war was given a fictional treatment in “Blood Diamond”, a film starring the Hollywood actor Leonardo DiCaprio.

Ernest Bai Koroma, the president of Sierra Leone, promised that the auction of the diamond would be transparent and praised Mr Momoh “for not smuggling the diamond out of the country”. He also promised that Mr Momoh would be rewarded.

Although big, the diamond is still dwarfed by the 3,106-carat Cullinan Diamond discovered in South Africa in 1905 and never matched since. It was later cut into several gems, two of which have been set into the Crown Jewels.